This invention relates to a protective guide for a flexible, elongated article such as a wire cable, a hydraulic hose, a pneumatic hose, or the like. The flexible, elongated article which is accommodated and supported within the guide is typically fixed at one end while the other end is movable.
There are various types of known protective guides for flexible, elongated articles. The guides are typically made of metal or plastics. Plastic protective guides in which each component is molded of synthetic resin are disclosed in Japanese Patent Publication (Kokoku) No. Hei 2-40135 and Japanese Laid-open (Kokai) Patent Publication No. Hei 10-28310.
The protective cable guide described in Hei 2-40135 is composed of link bodies each having a pair of plastic side plates. Link bodies are connected to one another by the engagement of protrusions formed in one link body with holes formed in side plates of an adjacent link body so that the link bodies are pivotally attached to each other.
On the other hand, the protective guide described in Hei 10-28310 is a belt-type guide comprising a plastic bottom wall, and side walls extending perpendicularly from the bottom wall, each side wall being split by grooves.
In the first of the above two conventional protective cable guides, where the link bodies are connected by pivoting attachment between protrusions and holes, dust is generated as a result of wear occurring at the pivots during articulating movement, and noise due to friction is also generated. Furthermore, since the link bodies pivot freely, the guide can readily collapse from an unstable condition and strike a floor or other surface, generating a large amount of noise.
Furthermore, since the second of the above two conventional protective cable guides is a belt type guide, it is not possible to shorten or lengthen the guide.
Accordingly, a general object of the invention is to solve one or more of the above-mentioned problems encountered in prior art protective guides. More specifically, an object of the invention is to provide a protective guide that avoids the production of dust due to friction occurring in articulation of the guide. Another object is to prevent the generation of noise during high speed movement. Still another object is to provide a guide that can be easily lengthened or shortened by the removal or addition of guide components.
The protective guide in accordance with the invention comprises a plurality of links connected to one another, each link being formed by a pair of spaced and opposed side plates, a first connecting plate extending from an upper edge of one side plate to an upper edge of the other side plate and a second connecting plate extending from a lower edge of said one side plate to a lower edge of said other side plate. Each of the side plates is a unitary element including a connecting rod protruding from a first side edge thereof. The connecting rod includes a flexible portion. Each side plate also has a connecting recess formed in a second side edge opposite to the first side edge, into which a connecting rod of a side plate of an adjacent link extends, whereby adjacent links of the guide are articulably connected to one another.
Preferably, an enlarged engagement portion is formed at an end of each connecting rod, and the enlarged engagement portion fits into, and is secured to, an engagement opening of a side plate of an adjacent link.
In a preferred embodiment, the second side edge of each side plate comprises an inclined surface on one side of the connecting recess. This inclined surface is positioned for engagement by a portion of the first side edge of an adjacent side plate, and limits the articulation of adjacent links to a predetermined angle. The portion of the connecting recess, into which a connecting rod extends, preferably widens gradually in a direction toward the side plate having the connecting rod which it receives.
In a preferred embodiment each side plate includes a side wall cover on its outer surface, and adjacent connecting plates of adjacent links overlap each other.
When a movable end of the protective guide is reciprocated while a cable or other flexible, elongated element is disposed inside the guide, the guide can be bent, by virtue of the bending of flexible portions of the connecting rods, until portions of edges of the side plates of the links abut inclined surfaces of the side plates of adjacent links. Since the side plates and connecting rods of the links have no portions which rub against each other frictionally as the guide bends, no dust is generated. Furthermore, since the adjacent links are connected to each other by connecting rods having flexible portions integrally formed on the side plates, the upper edge portions of the side plates can smoothly abut against a floor surface, reducing the generation of noise. Additionally, links can be added or removed easily.